Professor Robert West, at University College London, has an interesting theory which suggests that glucose tablets can help smokers to quit. It is well known that when smokers quit smoking they put on weight, and that nicotine appears to act like a mild anorectic drug…it dulls the appetite. It has also been noted that smokers often crave high carbohydrate foods when they quit smoking. So it seems as though smoking dulls the hunger for carbohydrates. The glucose theory (or at least one version of it) suggests that when an addicted smoker quits smoking they experience a strong hunger/craving sensation, sometimes located in their stomach. When trying to interpret that sensation they think, “what am I craving? I just gave up cigarettes, it must be that.”
But part of the renewed craving is actually craving for carbohydrates (which had previously been dulled by nicotine). So if the recent ex-smoker takes some glucose tablets, it will satiate their craving for carbohydrates, and also help the person feel less severe overall cravings. In addition, there is fairly solid experimental evidence that glucose tablets and drinks can improve feelings of stress, irritability and improve mental performance and memory. Many of the things that glucose improves are also nicotine withdrawal symptoms, so it should be no surprise that glucose tablets may help a recent ex-smoker to cope with withdrawal.
But this is more than just a theory. Professor West has published a series of studies supporting the role of glucose tablets in reducing cigarette cravings and helping smokers to quit. These have included fairly large randomized placebo-controlled trials (which found that glucose tablets were at least as effective as the nicotine patch for smoking cessation), and placebo-controlled experimental studies which found that the glucose tablets reduced cigarette cravings. The data on glucose has not all been totally consistent. For example, a colleague and I published a paper a few years ago showing no significant effect of glucose tablets on cigarette cravings.
But just this month, Professor West published his biggest trial of glucose tablets for smoking cessation, in the journal, Psychopharmacology. In this study 928 smokers were randomly allocated to receive either glucose tablets or sorbitol (placebo) tablets to help them quit. During this study in the UK, the UK government approved the used of NRT and bupropion as covered medicines in the UK National Health Service. As a result, about half of the people in the study also used an approved smoking cessation medicine. So when the results were analyzed they examined those who only used counseling plus glucose/sorbitol tablets, and separately analyzed those who used another medicine (plus counseling), plus either glucose or sorbitol. The results were a little puzzling.
The 6-month quite rate was no higher for those receiving glucose tablets only (10.7%) as compared to those who only received sorbitol tablets (14.3%). However , among the 474 smokers who received NRT or bupropion (mainly nicotine patch or gum), those who were also given glucose tablets had a significantly higher quit rate (18.2%) as compared with those given placebo tablets, (12.2%). These results are puzzling to me, as I might have expected the effects of glucose to be higher when the person had no other medications, when they were the opposite.
So what does all this mean? First of all, it seems likely that any effect of glucose in helping a smoker to quit may be quite small…it is no wonder-cure. But my view is that there are enough studies out there with evidence of a clinically useful effect of glucose on cigarette craving and cessation, to warrant further studies. Part of the reason this could be useful is that glucose tablets are so cheap compared to most medicines. Another is that for some medicines it would be useful to have an adjunct that could be added on if craving became a severe problem.
For now, the evidence may not be sufficient to start advising smokers routinely to use glucose tablets. However, it seems clear that going on a low calorie weight loss diet when trying to quit smoking is probably not the best combination.
West R et al (2010). A randomized trial of glucose tablets to aid smoking cessation. Psychopharmacology, 207, 631-637.
This post, Could Sugar Pills Improve Smoking Cessation Rates?, was originally published on Healthine.com by Jonathan Foulds, Ph.D..